|Publication number||US6334266 B1|
|Application number||US 09/665,932|
|Publication date||1 Jan 2002|
|Filing date||20 Sep 2000|
|Priority date||20 Sep 1999|
|Publication number||09665932, 665932, US 6334266 B1, US 6334266B1, US-B1-6334266, US6334266 B1, US6334266B1|
|Inventors||Heiko D Moritz, Jonathan A. Talbott, Mohan Chandra, James A. Tseronis, Ijaz Jafri|
|Original Assignee||S.C. Fluids, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (42), Non-Patent Citations (1), Referenced by (83), Classifications (27), Legal Events (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This is a continuation in-part of Application No. U.S. 09/632,770, filed Aug. 4, 2000 and this application further claims the benefit of U.S. Provisional Application No. 60/155,454 filed Sep. 20, 1999.
1. Technical Field of the Invention
This invention relates to methods and apparatus for the fabrication of micro-electro-mechanical systems (MEMS), micro-opto-mechanical systems (MOEMS), surface micro machined systems, and similar wafer-mounted microstructures; and in particular to methods and apparatus for applying supercritical fluid drying techniques in the fabrication of microstructures.
2. Background Art
One method of manufacturing micro-electro-mechanical systems (MEMS) based devices is Sacrificial Surface Micromachining (SSM) or surface micromachining. FIG. 1 is a prior art illustration of a simple “anchored” SSM silicon based production process. In FIG. 1a, a substrate, such as Silicon, is deposited with a sacrificial material, such as grown Silicon Dioxide or SiO2. In FIG. 1b, the sacrificial material is etched to open a hole for the anchor of the structure. In FIG. 1c, a structural material such as polysilicon is deposited on the sacrificial material. In FIG. 1d, the sacrificial material is etched away to release the structural layer, creating the microstructure. These steps can be repeated to form more complex multilevel structures. Although SiO2 is a common material for a sacrificial layer, other materials like photoresists may be used in other applications.
After removal of the sacrificial material or sacrificial layer by etching or other methods the wafer has to be rinsed to remove any residual trace of the etch liquid. Rinsing usually is done with deionized water, which causes the problem of stiction upon drying.
Stiction or adhesion occurs when a “released” structure adheres to another surface. FIG. 2 gives a visual representation of stiction and how it is generated. FIG. 2a, shows a properly released cantilevered polysilicon beam with rinsing liquid still trapped under it. FIG. 2b, shows how the capillary force generated upon drying of the rinsing liquid pulls the beam towards the silicon substrate. FIG. 2c, shows how the beam sticks to the substrate, rendering the device flawed.
The capillary force, responsible for the deformation of a beam upon drying as illustrated in FIG. 2, is represented by the following equation:
where γ is the surface tension of the rinsing liquid, A is the surface area that the beam shares with the substrate, h is the height of the gap between the surface of the substrate and the beam, and θ1 and θ2 are the contact angles of the rinsing liquid with the substrate and the beam, respectively.
There are two methods of controlling the capillary force, (i) manipulating the contact angle of the rinsing liquid by modifying the surface tension of the rinsing liquid, or (ii) reducing or eliminating the surface tension γ. The first method can only minimize the capillary force since the conditions of the surfaces in contact with the rinsing liquid, determining the contact angle, can vary. In addition, the condition of the rinsing liquid can vary during its use and may lead to unpredictable stiction and loss of yield.
Working to find improvements to the controlled release of microstructures without subsequent sticking of these structures to the substrate, researchers at the University of California at Berkeley have developed a process for drying silicon wafers in a supercritical fluid environment. In it's supercritical state, γ, the surface tension is zero, and therefore capillary forces cannot be built up as can be easily seen in the equation. If it is now possible to keep the environment surrounding the structure in a state with γ=0 during the whole drying process, stiction never occurs. The supercritical fluid of choice was CO2, carbon dioxide, due to its low critical point, determined by a critical temperature TC of 31.1 degrees centigrade and a critical pressure pC of 1073 pounds per square inch over atmosphere.
Before CO2 can be applied for drying, an intermediate process step has to be introduced based on the fact, that water, the rinsing liquid applied after the sacrificial etch step, is not miscible with CO2. After rinsing, when the wafer still is wet with water, the water has to be replaced by a material that is miscible with CO2. This material can be methanol or any other material that is to 100% miscible with CO2. Furthermore, the wafer has to be kept submerged in methanol till it is safely deposited in the process chamber.
Using this laboratory method, a silicon wafer containing a pattern of microelectronic structure, having been fabricated in the conventional manner, but with the added step of replacing the rinsing liquid water by methanol, is introduced into a pressure vessel, with a horizontal orientation, submerged in methanol. To accomplish this, the pressure vessel is first filled with methanol. Then the operator quickly transfers the wafer into the vessel while deftly attempting to maintain a liquid layer of methanol on the wafer surface during this transport. The pressure vessel is then sealed, and a through-flow of liquid carbon dioxide is introduced for about 15 minutes. The methanol is rapidly absorbed into the liquid carbon dioxide and carried out of the pressure vessel. When the vessel has been entirely purged of methanol and is completely filled with pure liquid carbon dioxide, heat is applied uniformly for several minutes, causing the carbon dioxide to transition to its supercritical phase.
It is at this point that the benefit of the process is realized, as no liquid/vapor interface occurs during this transition. The CO2 is then slowly vented to atmosphere. With the temperature kept higher than the critical temperature during venting, CO2 does not experience a phase transition and remains in a state with the surface tension equal to zero.
The prior art pressure vessel used in the laboratory setup for demonstrating this process is shown in FIG. 3. As is readily apparent from the figure, a vessel that can be opened in cross section and when closed is subjected to elevated temperature and pressure to this extent must be of substantial construction, with a locking mechanism adequate to safely sustain the total pressure applied. In the laboratory set up, a circumferential pattern of 8 bolts is used to secure the top to the base of the vessel, to contain the high pressure. Heat is applied to the vessel by external heaters, and ports in the vessel admit and remove the materials of the process.
There are several obvious problems with the laboratory set up that must be addressed in order to make this process sufficiently cost-effective and efficient for use in a production environment. The device is not suitable for integration into a production line with automated means for inserting and removing wafers; there is no safe transfer mechanism to ensure that a liquid layer is maintained on the wafer during the transport or transfer process; the closing mechanism of the pressure vessel is manual and too slow; and the serially administered steps of the process are manually accomplished and too slow for production requirements. The device is also lacking the safeguards required by industrial standards and regulations for production requirements.
During manufacturing, once the sacrificial layer is removed, if for any reason the wafer becomes dry, it can result in stiction or adhesion of devices onto the wafer substrate. Hence the transport of wafer from one manufacturing step to another manufacturing step without causing stiction is always a problem, and usually has been dependent on operator efficiency resulting in low device yields.
The invention, in its simplest form, is an apparatus and method for implementing and improving on the prior art methods for the drying of micro-electro-mechanical structures on silicon wafers or other substrate material or drying of wafers in general.
It is therefore an object of the invention to provide a practical and safe production mechanism for the CO2 supercritical phase drying of wafers, and of microstructures on substrates.
It is a further object to provide for emplacement of the wafers or substrates into the pressure vessel submerged in a first process fluid or rinsing agent such as methanol, and to then directly displace the methanol with a second process fluid also in a liquid state, such as liquid carbon dioxide, this being connected within the pressure vessel and without disturbing the microstructures.
It is a yet further object to then elevate the second process fluid to supercritical state so as to cause the drying of the wafers with the benefits of the supercritical process, then reducing the pressure and temperature for recovery of the wafers.
Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description, wherein we have shown and described only a preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by me on carrying out our invention.
FIG. 1 is a prior art representation of the sequential steps in the manufacturing of a typical Sacrificial Surface Micromachined (SSM) microelectromechanical system (MEMS) based device.
FIG. 2 is a prior art representation of the sequential steps device manufactured using Sacrificial Surface Micromachining method for manufacturing MEMS based device, experiencing stiction in the drying process.
FIG. 3 is a perspective representation of the prior art laboratory apparatus for demonstrating the process of supercritical CO2 drying of microstructures.
FIG. 4 is a diagrammatic cross section view of the preferred embodiment apparatus of the invention, illustrated with the base plate in an open position relative to the inverted pressure vessel.
FIG. 5 is a diagrammatic cross section view of the embodiment of FIG. 4, in a partially closed position where vessel tubes and container tubes are extending downward, respectively outside and inside the container.
FIG. 6 is a diagrammatic cross section view of the embodiment of FIGS. 4 and 5, in a fully closed position, with the vessel and container tubes extending respectively to nearly the base plate and the bottom of the container.
FIG. 7 is a schematic representation of the fluid valve and piping assembly of the embodiment of FIGS. 4, 5 and 6.
The invention is susceptible of many variations. Accordingly, the drawings and following description of the preferred embodiment are to be regarded as illustrative in nature, and not as restrictive.
Referring to FIGS. 4, 5 and 6, they show a preferred embodiment of the apparatus of the invention in its open, semi-open and closed positions, respectively. The apparatus can be operated with base plate (10), stationary, and pressure chamber (11), vertically movable; or with both base plate and pressure chamber movable; or with pressure chamber (11) held stationary and base plate (10) being vertically movable. In this preferred embodiment, we describe a stationary pressure chamber and moveable base plate.
An advantage of the inverted pressure vessel is the reduction of any particulates generated by a removable top and falling into the process environment. An advantage of the inverted, stationary vessel and movable base plate is the relative ease of elevating the base plate to the vessel, and the absence of flexible connections for supplying and removing process materials from the vessel.
Referring to FIG. 6, it shows base plate (10) and pressure chamber (11) made of stainless steel and electro-polished. Base plate (10) and pressure chamber (11) are sealed using an O-ring seal (16). One or more wafers (13) are placed in a wafer cassette (14) which is made of quartz or stainless steel. The wafer cassette is aligned in container (12) using cassette alignment fixture (18). The container (12) is placed on the base plate (10) using a container alignment fixture (17). The container (12) is filled with a process fluid (15), such as methanol or acetone. The choice of such fluid depends on its miscibility with liquid carbon dioxide.
The system contains internal heat exchanger (9) for heating and cooling the process fluid, for which external connections are provided through heat exchanger inlet (7) and heat exchanger outlet (8). The system incorporates rupture disk (6) as a safety feature to prevent over pressurization. The system also contains four process fluid lines that terminate in vertically extending tubes inside the pressure vessel; container inlet tube (1), vessel inlet tube (2), container outlet tube (4) and vessel outlet tube (5). Another line off the pressure vessel is provided for initial air purging of the system; purge line (3).
Referring to FIG. 7, the layout of different system valves and plumbing is shown. Reservoir (28) contains CO2, which can be provided to process chamber of pressure vessel (10) at constant pressures higher than the critical point of CO2. The reservoir pressure is read at pressure gauge (27). The different components shown on the supply side are the main reservoir valve low flow (19), main reservoir valve high flow (35), and inline filter (30). The different valves connected to the chamber are the container inlet valve (21), vessel inlet valve (22), purge line valve (23), container outlet valve (24), vessel outlet valve (25), dual inlet valve (20), recovery inlet line valve low flow (31), and recovery inlet line valve high flow (34). Other components include rupture disk for safety (26), chamber pressure gauge (32), chamber pressure transducer (33) and separator and recovery system (29).
Describing now the methodology for using the apparatus, wafer cassette (14), containing wafers (13) immersed in methanol, is placed into a container (12) so that the liquid level is about 10 mm below the top of container (12), and about 10 mm above the top of wafers (13). The alignment of the wafer cassette to the container is done via cassette alignment fixture (18), and alignment of the container to the base plate is done via container alignment fixture (17), assuring that the container and the wafers are repeatably indexed to a precise location on base plate (10).
The drying process is then started by pressing the start button on an associated control panel, not shown here but fully appreciated by those skilled in the art. The control panel display will prompt for any operator intervention and provides readout on process status during the drying cycle. Pressing the start button raises base plate (10). The base plate and pressure chamber (11) meet and are sealed via o-ring (16), and a locking mechanism (not shown) is actuated to provide suitable resistance to opening of the pressure vessel under all process operating pressures.
As noted, pressure vessel (11) has multiple process material supply and removal lines that penetrate the vessel wall. Comparing FIGS. 4,5, and 6; notice that when base plate (10) is raised, vertically extending container inlet tube (1) and container outlet tube (4) which protrude downwardly from the roof of the chamber of pressure vessel (11), enter container (12) and extend to nearly the bottom of the container as base plate (10) is raised into place. At the same time, vertically extending vessel inlet tube (2) and vessel outlet tube (5) also protrude from the roof of the chamber of pressure vessel (11), not entering container (12) when the base plate (10) is raised, but extending outside the container nearly to the base plate, outside container (12).
Once the chamber of pressure vessel (11) is completely sealed, the main reservoir valve low flow (19), the dual inlet valve (20), the vessel inlet valve (22), the purge line valve (23), and the vessel outlet valve (25) are opened. The container inlet valve (21) and the container outlet valve (24) are closed. The recovery inlet valve low flow (31) and recovery inlet valve high flow (34) are both closed. It is important to pressurize the vessel slowly to avoid turbulence that might damage the microstructures on wafers (13). Carbon dioxide is introduced into the pressure chamber at a very slow rate, and the chamber pressure is monitored via readout from the pressure gauges (27), (32) and pressure transducers (33), (36). Since CO2 is heavier than air, it slowly pushes air out of the chamber through purge line (3). This ensures the removal of air from the chamber. Purging is done until the chamber is completely filled with CO2 and all air has been exhausted.
Next, the purge line valve (23) is closed, and the chamber is pressurized to about 700 psi. When 700 psi pressure is achieved, main reservoir valve high flow (35) is opened, and the chamber is pressurized faster to go to 1100 psi. Once the desired pressure is achieved, which is monitored via chamber pressure transducer (33) as well as chamber pressure gauge (32), the dual inlet valve (20), and vessel outlet valve (25), are closed. The system at this point contains methanol contained in the container and liquid CO2, surrounding the container in the chamber.
The next step is removal of methanol from the system and its replacement with liquid CO2. To do this, the container outlet valve (24), and the recovery inlet valve low flow (31), are opened, whereas vessel outlet valve (25) remains closed. The siphon action of the container outlet tube (4) ensures the flow of methanol from the vessel to the separator and recovery system. During this process step the methanol is continuously replaced by liquid CO2. The constant flow of CO2 via the vessel inlet tube (2) into the chamber finally results in removal of methanol from container (12).
The line coming from the recovery inlet line valve low flow (31) is monitored for end point detection to determine when the methanol has been replaced completely. Once no methanol is present, all system valves are closed. At this time the chamber is filled with liquid carbon dioxide at 1100 psi.
Next, using heat exchanger (9), the CO2 in the pressure vessel is heated to about 35-40 degree centigrade to transform the liquid CO2 into it's supercritical state. A thermocouple (not shown) is mounted within pressure vessel (11), which provides temperature information back to a system control computer. As heat is applied and the temperature of the CO2 is raised, there is a corresponding increase in pressure. If the pressure reaches a value above a set point pressure calculated to be the maximum safe operating pressure for pressure vessel (11), the recovery inlet high flow valve (34) is opened to relieve the pressure.
Once the supercritical state is achieved, the container outlet valve (24), vessel outlet valve (25), recovery inlet valve high flow (34), are opened to achieve atmospheric pressure. As soon as the atmospheric pressure is achieved, the heat exchanger switches to cooling mode to bring the vessel to less than 25 degree centigrade. This ensures that at the start of the next cycle, the vessel will be at lower than critical temperature condition. The pressure vessel can now be opened, and wafer carrier (14) can be removed manually or by automatic means, leaving the system ready for the next drying cycle.
As will be realized, the invention is capable of other and different embodiments, including configurations adapted to handling wafers horizontally, as in a vertically stacked wafer cassette. Its several details are capable of modifications in various obvious respects, all without departing from the essence of the invention.
For example, there may be an apparatus for drying wafers in a supercritical environment, consisting of an inverted pressure vessel, a horizontal base plate, a wafer cassette configured for supporting at least one wafer for drying, a container sufficiently large to submerge the wafer cassette and at least one wafer in a first process fluid such as methanol, and where the container is also sufficiently small enough to fit on the base plate and within the pressure vessel. The apparatus may include a way for aligning the wafer cassette within the container, such as a simple fixture on the bottom of the container, and a way for aligning the container on the base plate, again such as a simple fixture on the base plate. The apparatus may also have an elevator or screw assembly or other lift and lock mechanism for bringing the pressure vessel and base plate into a closed and sealed relationship.
The apparatus may further include a way for displacing the air in the pressure vessel with a second process fluid in a gaseous state, such as Carbon Dioxide, and a way to elevate the second process fluid to a liquid state, and then displace the first process fluid in the container with the second process fluid without any intervening contact of the wafer by air or other substances. The apparatus may further include a way for elevating the second process fluid to a supercritical state, and then reducing pressure in the pressure vessel to ambient pressure. There may also be a way for cooling the remaining second process fluid to below its supercritical temperature.
Another example of the apparatus within the scope of the invention includes vertically downwardly extending vessel inlet and outlet tubes, where the tubes terminate outside the container and near the base plate, and a purge line outlet and associated valve at the roof of the pressure vessel. There may also be vertically downwardly extending container inlet and outlet tubes, where these tubes terminate inside the container and near the bottom of the container.
In yet another example, the pressure vessel may include an internal capability for heating and cooling, such as a heat exchanger connected to external sources of heated and cooled fluids, so that it can be operated in a heating or cooling mode. There may also be a purge line at the top of the pressure vessel and an associated purge line valve for venting the pressure vessel. And the apparatus may be set up with associated equipment for automatic loading of the pressure vessel with wafers submerged in the first process fluid.
As yet a further example, there is within the scope of the invention a method for drying wafers in a supercritical environment, consisting of using an apparatus of the invention and aligning a wafer cassette within the container, submerged in a first process fluid, aligning the container on the base plate, bringing the pressure vessel and base plate into a closed and sealed relationship, and displacing the air in the pressure vessel with a second process fluid in a gaseous state. The method may include elevating the second process fluid to a liquid state, displacing the first process fluid in the container with the second process fluid in its liquid state. The method may then include the steps of elevating the second process fluid to a supercritical state so as to dry the wafers, then reducing the pressure in the pressure vessel to ambient pressure, and cooling the second process fluid to below supercritical temperature.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3744660||30 Dec 1970||10 Jul 1973||Combustion Eng||Shield for nuclear reactor vessel|
|US3968885||27 Aug 1974||13 Jul 1976||International Business Machines Corporation||Method and apparatus for handling workpieces|
|US4245154||28 Jun 1978||13 Jan 1981||Tokyo Ohka Kogyo Kabushiki Kaisha||Apparatus for treatment with gas plasma|
|US4355937||24 Dec 1980||26 Oct 1982||International Business Machines Corporation||Low shock transmissive antechamber seal mechanisms for vacuum chamber type semi-conductor wafer electron beam writing apparatus|
|US4422651||27 Dec 1978||27 Dec 1983||General Descaling Company Limited||Closure for pipes or pressure vessels and a seal therefor|
|US4522788||5 Mar 1982||11 Jun 1985||Leco Corporation||Proximate analyzer|
|US4626509||11 Jul 1983||2 Dec 1986||Data Packaging Corp.||Culture media transfer assembly|
|US4789077||24 Feb 1988||6 Dec 1988||Public Service Electric & Gas Company||Closure apparatus for a high pressure vessel|
|US4823976||4 May 1988||25 Apr 1989||The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration||Quick actuating closure|
|US4827867||21 Nov 1986||9 May 1989||Daikin Industries, Ltd.||Resist developing apparatus|
|US4879431||9 Mar 1989||7 Nov 1989||Biomedical Research And Development Laboratories, Inc.||Tubeless cell harvester|
|US5071023||7 Sep 1990||10 Dec 1991||Societe Nouvelle Clera||Device for manually opening and closing a vessel door|
|US5071485||11 Sep 1990||10 Dec 1991||Fusion Systems Corporation||Method for photoresist stripping using reverse flow|
|US5167716||28 Sep 1990||1 Dec 1992||Gasonics, Inc.||Method and apparatus for batch processing a semiconductor wafer|
|US5169408||26 Jan 1990||8 Dec 1992||Fsi International, Inc.||Apparatus for wafer processing with in situ rinse|
|US5191993||24 Feb 1992||9 Mar 1993||Xorella Ag||Device for the shifting and tilting of a vessel closure|
|US5221019||7 Nov 1991||22 Jun 1993||Hahn & Clay||Remotely operable vessel cover positioner|
|US5224504||30 Jul 1992||6 Jul 1993||Semitool, Inc.||Single wafer processor|
|US5236669||8 May 1992||17 Aug 1993||E. I. Du Pont De Nemours And Company||Pressure vessel|
|US5251776||12 Aug 1991||12 Oct 1993||H. William Morgan, Jr.||Pressure vessel|
|US5280693||7 Oct 1992||25 Jan 1994||Krones Ag Hermann Kronseder Maschinenfabrik||Vessel closure machine|
|US5314574||25 Jun 1993||24 May 1994||Tokyo Electron Kabushiki Kaisha||Surface treatment method and apparatus|
|US5433334||8 Sep 1993||18 Jul 1995||Reneau; Raymond P.||Closure member for pressure vessel|
|US5571330||12 Nov 1993||5 Nov 1996||Asm Japan K.K.||Load lock chamber for vertical type heat treatment apparatus|
|US5589224||22 Sep 1994||31 Dec 1996||Applied Materials, Inc.||Apparatus for full wafer deposition|
|US5621982||27 Oct 1994||22 Apr 1997||Shinko Electric Co., Ltd.||Electronic substrate processing system using portable closed containers and its equipments|
|US5644855||6 Apr 1995||8 Jul 1997||Air Products And Chemicals, Inc.||Cryogenically purged mini environment|
|US5706319||12 Aug 1996||6 Jan 1998||Joseph Oat Corporation||Reactor vessel seal and method for temporarily sealing a reactor pressure vessel from the refueling canal|
|US5746008||24 Feb 1997||5 May 1998||Shinko Electric Co., Ltd.||Electronic substrate processing system using portable closed containers|
|US5900107||11 Sep 1996||4 May 1999||Essef Corporation||Fitting installation process and apparatus for a molded plastic vessel|
|US5934991||1 Feb 1998||10 Aug 1999||Fortrend Engineering Corporation||Pod loader interface improved clean air system|
|US5989342||28 Jan 1997||23 Nov 1999||Dainippon Screen Mfg, Co., Ltd.||Apparatus for substrate holding|
|US5992680||29 Jan 1997||30 Nov 1999||Smith; Philip E.||Slidable sealing lid apparatus for subsurface storage containers|
|US6029371||16 Sep 1998||29 Feb 2000||Tokyo Electron Limited||Drying treatment method and apparatus|
|US6053348||31 Dec 1997||25 Apr 2000||Morch; Leo||Pivotable and sealable cap assembly for opening in a large container|
|US6085935||10 Aug 1998||11 Jul 2000||Alliance Laundry Systems Llc||Pressure vessel door operating apparatus|
|US6097015||14 Oct 1998||1 Aug 2000||Healthbridge, Inc.||Microwave pressure vessel and method of sterilization|
|US6128830 *||15 May 1999||10 Oct 2000||Dean Bettcher||Apparatus and method for drying solid articles|
|US6164297 *||12 Jun 1998||26 Dec 2000||Tokyo Electron Limited||Cleaning and drying apparatus for objects to be processed|
|US6216364 *||14 Apr 1999||17 Apr 2001||Kaijo Corporation||Method and apparatus for drying washed objects|
|EP0903775A2||17 Sep 1998||24 Mar 1999||Tokyo Electron Limited||Drying treatment method and apparatus|
|JPH01246835A||Title not available|
|1||PCT International Search Report dated May 31, 2001 of International Application No. PCT/US00/03796 filed Feb. 5, 2001.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US6398875 *||27 Jun 2001||4 Jun 2002||International Business Machines Corporation||Process of drying semiconductor wafers using liquid or supercritical carbon dioxide|
|US6554507 *||20 Dec 2001||29 Apr 2003||Nippon Telegraph And Telephone Corporation||Pattern formation method and apparatus|
|US6576066 *||28 Nov 2000||10 Jun 2003||Nippon Telegraph And Telephone Corporation||Supercritical drying method and supercritical drying apparatus|
|US6593749 *||31 May 2001||15 Jul 2003||Innovative Micro Technology||Wafer level method for probing micromechanical devices|
|US6656666 *||22 Dec 2000||2 Dec 2003||International Business Machines Corporation||Topcoat process to prevent image collapse|
|US6722642||6 Nov 2002||20 Apr 2004||Tokyo Electron Limited||High pressure compatible vacuum chuck for semiconductor wafer including lift mechanism|
|US6729040 *||9 Mar 2001||4 May 2004||Oliver Design, Inc.||Apparatus and method for drying a substrate using hydrophobic and polar organic compounds|
|US6736149||19 Dec 2002||18 May 2004||Supercritical Systems, Inc.||Method and apparatus for supercritical processing of multiple workpieces|
|US6748960||1 Nov 2000||15 Jun 2004||Tokyo Electron Limited||Apparatus for supercritical processing of multiple workpieces|
|US6837253 *||22 Apr 2002||4 Jan 2005||Imtec Acculine, Inc.||Processing tank with improved quick dump valve|
|US6871656 *||25 Sep 2002||29 Mar 2005||Tokyo Electron Limited||Removal of photoresist and photoresist residue from semiconductors using supercritical carbon dioxide process|
|US6895979 *||6 Feb 2003||24 May 2005||Tokyo Electron Limited||Processing apparatus and processing method|
|US7077917 *||10 Feb 2003||18 Jul 2006||Tokyo Electric Limited||High-pressure processing chamber for a semiconductor wafer|
|US7146991||15 Jan 2003||12 Dec 2006||Cinetic Automation Corporation||Parts washer system|
|US7338565 *||18 Jan 2006||4 Mar 2008||Cinetic Automation Corporation||Housingless washer|
|US7353832 *||21 Aug 2003||8 Apr 2008||Cinetic Automation Corporation||Housingless washer|
|US7414015 *||28 Apr 2006||19 Aug 2008||The Regents Of The University Of Michigan||Metal working lubricant formulations based on supercritical carbon dioxide|
|US7445015 *||30 Sep 2004||4 Nov 2008||Lam Research Corporation||Cluster tool process chamber having integrated high pressure and vacuum chambers|
|US7503334||6 Jan 2005||17 Mar 2009||Novellus Systems, Inc.||Apparatus and methods for processing semiconductor substrates using supercritical fluids|
|US7767145||28 Mar 2005||3 Aug 2010||Toyko Electron Limited||High pressure fourier transform infrared cell|
|US7789971||13 May 2005||7 Sep 2010||Tokyo Electron Limited||Treatment of substrate using functionalizing agent in supercritical carbon dioxide|
|US7797855 *||18 Aug 2006||21 Sep 2010||Tokyo Electron Limited||Heating apparatus, and coating and developing apparatus|
|US7866058 *||30 Aug 2007||11 Jan 2011||Semes Co., Ltd.||Spin head and substrate treating method using the same|
|US7900373 *||15 Apr 2003||8 Mar 2011||Ers Electronic Gmbh||Method for conditioning semiconductor wafers and/or hybrids|
|US8167092 *||1 Aug 2008||1 May 2012||The Regents Of The University Of Michigan||Metalworking lubricant formulations based on supercritical carbon dioxide|
|US8235061 *||28 Jun 2010||7 Aug 2012||Tokyo Electron Limited||Substrate processing apparatus and substrate processing method|
|US8944078 *||1 Apr 2011||3 Feb 2015||Tokyo Electron Limited||Substrate processing apparatus, substrate processing method and storage medium|
|US8961701 *||18 Sep 2009||24 Feb 2015||Lam Research Corporation||Method and system of drying a microelectronic topography|
|US9004079 *||1 Apr 2011||14 Apr 2015||Tokyo Electron Limited||Substrate processing apparatus|
|US20020046707 *||24 Jul 2001||25 Apr 2002||Biberger Maximilian A.||High pressure processing chamber for semiconductor substrate|
|US20020189543 *||10 Apr 2002||19 Dec 2002||Biberger Maximilian A.||High pressure processing chamber for semiconductor substrate including flow enhancing features|
|US20030027085 *||25 Sep 2002||6 Feb 2003||Mullee William H.||Removal of photoresist and photoresist residue from semiconductors using supercritical carbon dioxide process|
|US20030121534 *||19 Dec 2002||3 Jul 2003||Biberger Maximilian Albert||Method and apparatus for supercritical processing of multiple workpieces|
|US20030127117 *||6 Feb 2003||10 Jul 2003||Kyouji Kohama||Processing apparatus and processing method|
|US20030136424 *||15 Jan 2003||24 Jul 2003||Stockert David L.||Parts washer system|
|US20030136514 *||15 Jan 2003||24 Jul 2003||Biberger Maximilian Albert||Method of supercritical processing of a workpiece|
|US20030150559 *||6 Mar 2003||14 Aug 2003||Biberger Maximilian Albert||Apparatus for supercritical processing of a workpiece|
|US20030155541 *||12 Feb 2003||21 Aug 2003||Supercritical Systems, Inc.||Pressure enhanced diaphragm valve|
|US20040003831 *||2 Jul 2003||8 Jan 2004||Mount David J.||Supercritical fluid cleaning process for precision surfaces|
|US20040040660 *||3 Oct 2001||4 Mar 2004||Biberger Maximilian Albert||High pressure processing chamber for multiple semiconductor substrates|
|US20040157463 *||10 Feb 2003||12 Aug 2004||Supercritical Systems, Inc.||High-pressure processing chamber for a semiconductor wafer|
|US20040211447 *||28 Apr 2003||28 Oct 2004||Supercritical Systems, Inc.||Apparatus and method of securing a workpiece during high-pressure processing|
|US20050000651 *||21 Jul 2004||6 Jan 2005||Biberger Maximilian A.||High pressure processing chamber for semiconductor substrate|
|US20050034660 *||11 Aug 2003||17 Feb 2005||Supercritical Systems, Inc.||Alignment means for chamber closure to reduce wear on surfaces|
|US20050039784 *||21 Aug 2003||24 Feb 2005||Stockert David L.||Housingless washer|
|US20050227503 *||15 Apr 2003||13 Oct 2005||Erich Reitinger||Method and device for conditioning semiconductor wafers and/or hybrids|
|US20060003592 *||30 Jun 2004||5 Jan 2006||Tokyo Electron Limited||System and method for processing a substrate using supercritical carbon dioxide processing|
|US20060065287 *||30 Sep 2004||30 Mar 2006||Lam Research Corporation||Cluster tool process chamber having integrated high pressure and vacuum chambers|
|US20060065288 *||30 Sep 2004||30 Mar 2006||Darko Babic||Supercritical fluid processing system having a coating on internal members and a method of using|
|US20060068583 *||29 Sep 2004||30 Mar 2006||Tokyo Electron Limited||A method for supercritical carbon dioxide processing of fluoro-carbon films|
|US20060102204 *||12 Nov 2004||18 May 2006||Tokyo Electron Limited||Method for removing a residue from a substrate using supercritical carbon dioxide processing|
|US20060102208 *||12 Nov 2004||18 May 2006||Tokyo Electron Limited||System for removing a residue from a substrate using supercritical carbon dioxide processing|
|US20060102590 *||15 Feb 2005||18 May 2006||Tokyo Electron Limited||Method for treating a substrate with a high pressure fluid using a preoxide-based process chemistry|
|US20060102591 *||12 Nov 2004||18 May 2006||Tokyo Electron Limited||Method and system for treating a substrate using a supercritical fluid|
|US20060104831 *||12 Nov 2004||18 May 2006||Tokyo Electron Limited||Method and system for cooling a pump|
|US20060130875 *||22 Dec 2004||22 Jun 2006||Alexei Sheydayi||Method and apparatus for clamping a substrate in a high pressure processing system|
|US20060130913 *||22 Dec 2004||22 Jun 2006||Alexei Sheydayi||Non-contact shuttle valve for flow diversion in high pressure systems|
|US20060130966 *||20 Dec 2004||22 Jun 2006||Darko Babic||Method and system for flowing a supercritical fluid in a high pressure processing system|
|US20060134332 *||22 Dec 2004||22 Jun 2006||Darko Babic||Precompressed coating of internal members in a supercritical fluid processing system|
|US20060135047 *||22 Dec 2004||22 Jun 2006||Alexei Sheydayi||Method and apparatus for clamping a substrate in a high pressure processing system|
|US20060180174 *||15 Feb 2005||17 Aug 2006||Tokyo Electron Limited||Method and system for treating a substrate with a high pressure fluid using a peroxide-based process chemistry in conjunction with an initiator|
|US20060180175 *||15 Feb 2005||17 Aug 2006||Parent Wayne M||Method and system for determining flow conditions in a high pressure processing system|
|US20060180181 *||18 Jan 2006||17 Aug 2006||Stockert David L||Housingless washer|
|US20060180572 *||15 Feb 2005||17 Aug 2006||Tokyo Electron Limited||Removal of post etch residue for a substrate with open metal surfaces|
|US20060180573 *||15 Feb 2005||17 Aug 2006||Tokyo Electron Limited||Method and system for treating a substrate with a high pressure fluid using fluorosilicic acid|
|US20060247139 *||28 Apr 2006||2 Nov 2006||Skerlos Steven J||Metal working lubricant formulations based on supercritical carbon dioxide|
|US20060254615 *||13 May 2005||16 Nov 2006||Tokyo Electron Limited||Treatment of substrate using functionalizing agent in supercritical carbon dioxide|
|US20060255012 *||10 May 2005||16 Nov 2006||Gunilla Jacobson||Removal of particles from substrate surfaces using supercritical processing|
|US20060266287 *||25 May 2005||30 Nov 2006||Parent Wayne M||Method and system for passivating a processing chamber|
|US20070012337 *||15 Jul 2005||18 Jan 2007||Tokyo Electron Limited||In-line metrology for supercritical fluid processing|
|US20070034237 *||17 Oct 2006||15 Feb 2007||Stockert David L||Parts washer method|
|US20070037399 *||13 Nov 2003||15 Feb 2007||Christoph Luetge||High-pressure device for closing a container in a clean room|
|US20070048979 *||18 Aug 2006||1 Mar 2007||Tokyo Electron Limited||Heating apparatus, and coating and developing apparatus|
|US20080052948 *||30 Aug 2007||6 Mar 2008||Semes Co., Ltd||Spin head and substrate treating method using the same|
|US20080293599 *||1 Aug 2008||27 Nov 2008||Skerlos Steven J||Metalworking lubricant formulations based on supercritical carbon dioxide|
|US20100000681 *||7 Jan 2010||Supercritical Systems, Inc.||Phase change based heating element system and method|
|US20100071726 *||18 Sep 2009||25 Mar 2010||Lam Research Corporation||Method and system of drying a microelectronic topography|
|US20110000512 *||6 Jan 2011||Tokyo Electron Limited||Substrate processing apparatus and substrate processing method|
|US20110240066 *||6 Oct 2011||Tokyo Electron Limited||Substrate processing apparatus, substrate processing method and storage medium|
|US20110247662 *||13 Oct 2011||Tokyo Electron Limited||Substrate processing apparatus|
|US20140291421 *||24 Feb 2014||2 Oct 2014||Samsung Electronics Co., Ltd.||Substrate Treating Apparatus|
|WO2004073036A2 *||9 Feb 2004||26 Aug 2004||Supercritical Systems Inc||High-pressure processing chamber for a semiconductor wafer|
|WO2006119047A3 *||28 Apr 2006||9 Aug 2007||Univ Michigan||Metalworking lubricant formulations based on supercritical carbon dioxide|
|U.S. Classification||34/337, 34/218, 34/343, 34/62, 34/467, 118/725, 34/393, 414/811, 134/902|
|International Classification||H01L21/304, B01J3/06, F26B9/06, H01L21/00, F26B5/14, B01J3/00, H01L21/677|
|Cooperative Classification||Y10S134/902, B01J3/06, B01J3/008, H01L21/67757, H01L21/67034, H01L21/67126|
|European Classification||H01L21/67S2D4D, H01L21/67S2M, H01L21/677B12, B01J3/00S, B01J3/06|
|12 Dec 2000||AS||Assignment|
|20 Aug 2002||CC||Certificate of correction|
|20 Jul 2005||REMI||Maintenance fee reminder mailed|
|3 Jan 2006||LAPS||Lapse for failure to pay maintenance fees|
|28 Feb 2006||FP||Expired due to failure to pay maintenance fee|
Effective date: 20060101